Geotechnical Excellence Beneath Kosciuszko with Snowy 2.0 project

Australia’s most ambitious renewable energy initiative, Snowy 2.0, continues to make strong progress despite facing a few geological and environmental setbacks. The project, which links the Tantangara and Talbingo dams via a network of tunnels and an underground power station, will ultimately deliver 2,200 megawatts of pumped-hydro energy to the national grid.

At the heart of the tunneling operations are three major TBMs. TBM Florence has resumed work on the 17 km headrace tunnel after a temporary stoppage caused by a sinkhole. TBM Lady Eileen Hudson has already completed 85% of the 6 km tailrace tunnel, and TBM Kirsten has begun boring the steep Inclined Pressure Shaft, with 14% already excavated.

Work on the power station caverns is also advancing. Excavation and rock reinforcement are more than 35% complete, with the transformer hall nearly halfway excavated by volume. Meanwhile, the machine hall has reached a depth of 28 meters. These massive chambers are being accessed through drill-and-blast tunnels, 93% of which are finished.

The Marica surge shaft, a critical feature that will manage water pressure during plant startup and shutdown, has surpassed 150 meters of excavation and will become one of the world’s deepest and widest operational shafts.

Above ground, construction at the upper and lower reservoir intakes is also progressing, supported by tower cranes and large-scale concrete works. More than 6,600 m³ of concrete has been poured at the Tantangara intake site.

To strengthen delivery timelines and navigate complex fault zones, Snowy Hydro has gained approval to deploy a fourth TBM, set to begin excavation by the end of 2025. With operations now fully resumed, Snowy 2.0 is well-positioned to play a pivotal role in Australia’s clean energy future.